The flight crew of a medevac helicopter has just received a request for a medevac resulting from a serious motor vehicle accident at the intersection of two major state highways. In less than five minutes, the helicopter is airborne with an estimated time of arrival of 12 minutes. Once aloft...
To access the remainder of this piece of premium content, you must be registered with Firehouse. Already have an account? Login
Register in seconds by connecting with your preferred Social Network.
Complete the registration form.
Using roadmaps to provide latitude and longitude coordinates to a helicopter crew provides highly inaccurate information. Vehicles equipped with GPS receivers provide the flight crew with much more accurate landing zone coordinates (within 100 feet), which greatly lessens the helicopter's response time. Also, vehicle GPS receivers will eliminate the confusion associated with finding an unfamiliar landing zone that manifests itself in the form of a radio exchange between the flight crew and landing zone fire personnel in the following form: The helicopter crew asks the fire personnel if they see the helicopter. The fire personnel responses can include, "yes, turn right" or "we are off your left side near a white house." The flight crew members spend valuable time visually searching for the unfamiliar landing zone when they need to be looking for obstacles such as towers, wires and other aircraft.
Although not obvious to the ground personnel, the flight crew may see 20 or 30 white houses off the left side of the helicopter. With trees blocking the ground equipment from the aircraft, it can be difficult for the flight crew to pick out the correct white house. This type of radio exchange is distracting to the flight crew when it is preparing to land the helicopter, one of the most critical and dangerous aspects of the flight.
GPS consists of a constellation of 24 satellites in earth orbit. The system was developed and placed into orbit by the U.S. Air Force. At all times, a minimum of six satellites above the horizon transmit signals that provide highly accurate latitude and longitude coordinates as well as time and elevation information. During the Persian Gulf War, GPS navigation information let U.S. aircraft to drop ordnance with unprecedented accuracy. Since then, the use of GPS navigation information by emergency services agencies as well as civilian companies has skyrocketed.
Thanks to mass production, vehicle GPS receivers are inexpensive, costing from $100 to $450, depending on the features offered. A vehicle GPS receiver should:
- Have an external antenna to allow quicker acquisition of the satellites.
- Be rugged and have a vehicle mounting bracket with a power supply cable so that the unit can be powered in the same manner as the vehicle's radios.
- Be simple to operate.
Most vehicle GPS receivers require only the pushing of the "on" button to be operational. When the satellites are acquired, the display indicates the present position in latitude and longitude of the vehicle, whether moving or stationary.
When a fire apparatus or ambulance equipped with a vehicle GPS receiver responds to an incident, the driver needs only to turn on the GPS receiver when leaving the station. The GPS receiver will acquire the satellites within two minutes and continually display the position of the fire apparatus or ambulance in latitude and longitude as it travels to the scene. When the vehicle stops at the landing zone, the driver contacts the helicopter crew and passes the location of the landing zone in latitude and longitude "North 3838. 45 West 7721. 35." The flight crew programs the landing zone coordinates into the helicopter navigation computer and the site is found quickly.
Initial and recurrent training is important with any new piece of equipment. If your company installs a vehicle GPS receiver, contact a flight crew from a helicopter that serves your area and schedule a drill. A drill with one helicopter and several fire companies would be best. It's suggested that the drill consist of actual dispatches of the helicopter with vehicle-derived GPS latitude and longitude coordinates transmitted by the fire personnel to the helicopter, with the helicopter then flying over the vehicle's precise location.
David C. Delisio is a civilian pilot flying the SA 365 Dauphin 2 helicopter for the Aviation Division of the Maryland State Police, assigned to Trooper 3 in Frederick. He has been flying helicopters for 18 years and has extensive experience flying medevac and search-and-rescue helicopters in the U.S. Air Force, U.S. Coast Guard, U.S. Army National Guard and Maryland State Police.